As computer processor speeds continue to increase, the need for reliable high data transfer rates between interconnected devices becomes more critical. This includes communication between networked devices, as well as between a specific device and its peripheral components (i.e., I/O connections).
Systems and interfaces were developed to provide faster data transfer between devices to meet the increased demand for speed. However, the development of different systems resulted in many different standards, protocols and requirements. Thus, compatibility became a problem.
In the 1980's, the Small Computer Systems Interface (SCSI) standard was developed to provide faster data transfer between devices. The original SCSI interface (i.e., SCSI-1) provided a high-speed (e.g., 5 MB/sec) parallel interface for connecting numerous devices. Subsequently, improved SCSI interfaces were developed providing data transfer rates up to 80 MB/sec. SCSI technology was implemented in many devices, including many peripheral components, such as, for example, disk drives, CD-ROM drives, scanners and printers. However, SCSI does not always meet the rapidly increasing data transfer demands of many of present computer systems. Further, SCSI interfaces have very limited bus lengths. Thus, for example, for systems requiring interconnection of devices in separate buildings, a SCSI interface is not capable of providing communication. Further, expensive connectors or cables may be required.
A higher bandwidth protocol independent system was needed to meet the demands of the increasing performance in computers, processors and peripheral devices. In response to the increased demands, Fibre Channel technology was developed and provides high speed, scalable communication between computer devices, particularly in systems requiring the transfer of large amounts of data and/or requiring transfer of data over a substantial distance. Fibre Channel technology provides a high bandwidth flexible interface and serial data transfer architecture that meets the demands of the high-speed data transfer requirements of present computer systems. This technology supports data transfer over longer distances and supports multiple data rates, media types and connection types.
As a result of the high-speed transfer capabilities of Fibre Channel technology, interconnection devices for systems using this technology must also support these high speeds. For example, a switch, router or hub for controlling data transfer in a Fibre Channel system must have the capability to support bandwidth rates of over one gigahertz (Ghz). Further, the transmitter at one port of the system and the receiver at another port of the system must support this high speed data transfer.
The problem with the communicating devices (i.e., transmitter and receiver) in a Fibre Channel system is that the speed requirements limit the types of material that can be used to support the high bandwidth. With respect specifically to transmitting and receiving data within a Fibre Channel system, most transmitters, receivers and/or transceivers (“communication devices”) are implemented using higher performance process technologies, such as Gallium Arsenide, which are particularly useful for high-speed electronic switching applications. Additionally, these communication devices are normally monolithic implementations. Thus, present Fibre Channel communication devices capable of operating at speeds of greater than one gigabits per second (Gbps) are typically implemented as discrete Integrated Circuits (ICs) in process technologies capable of supporting GHz frequencies (e.g., Gallium Arsenide).
For example, IC Fibre Channel transceivers are used to translate high speed Fibre Channel serial data to low speed Fibre Channel parallel data for protocol processing. Further, low speed Fibre Channel parallel data from a protocol processor is translated into high speed Fibre Channel serial data for transmission along the physical medium (e.g., fiber optic cable). Because most Fibre Channel protocol processor Application Specific ICs (ASICs) are highly complex digital devices, they are typically implemented in CMOS technologies for low power, high yield and low cost. Thus, present Fibre Channel transceivers are not adapted for integration into Fibre Channel protocol processor ASICs. These devices must be manufactured separately, thereby resulting in multiple packaging of the devices, with an increase in cost.
Thus, in order to reduce complexity and cost, it is desirable to provide a Fibre Channel transceiver as a core module adapted for integration into lower performance process technology devices, such as a Fibre Channel protocol processor ASIC.